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Finding information

After selecting the sources it is time to search in the different systems (Library Catalog, databases, Internet, etc.) using the most appropriate search strategies. For this purpose, it is useful to get acquainted with some rules of syntax (which define the best use of search operators for creating good queries).

Below you will find some common search strategies that can be used in most systems and that allow you to extend or narrow the search in order to obtain more relevant results.

Most common search strategies


What does it do?     Example Results Check out!
AND narrows the search Wind AND Energy Both terms must appear
OR extends the search Wind OR Energy

Either both terms or only one of them will appear

NOT narrows the search Wind NOT Energy

The term after the operator is excluded

The use of certain symbols associated with a term can retrieve different variants of a word:

  • Example: searching for: comput* retrieves computer, computers, computing, etc.

Attentio: the symbol which represents the truncation may vary from system to system. The most common symbols are the asterisk (*), the question mark (?) or the dollar ($).


Operator   What does it do? Example


* extends the search    energy*         retrieves energy, energetic, energize, etc.   


Quotation marks are used when we need to search for a phrase.

  • Example: when searching for “renewable energy”, the system will only retrieve the results which contain this exact expression, in which both words appear by the given order.

It will therefore retrieve documents which are more relevant than if searching without quotation marks.

Operator What does it do? Example


"..." narrows the search   "wind energy"           retrieves the exact expression given within quotation marks

See this example!

This video illustrates the search strategies shown previously:

Yavapai College Library. 2011. "Searching Databases". Youtube video, 4:55.

Did you know?


Some search systems have features like Thesaurus (structured list of keywords) to help obtaining more relevant results.

One example is Engineering Village, an engineering database subscribed by FEUP.


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